The Canon RF 10-20mm f/4 L IS STM delivers professional quality results for all your landscape, nature, architecture, and interior image-making needs. Optimized for both photo and video applications, this versatile, full-frame, L-series lens provides visual drama to your imagery for outstanding results that will be remembered for a lifetime. Fast and precise autofocus system delivering quick, nearly-silent autofocus performance with full-time manual focus override. Quiet high-speed STM leadscrew-type focus drive system that is especially beneficial to video users. Optical Image Stabilizer minimizes the appearance of camera shake by five stops to better enable working in low-light conditions and with slower shutter speeds. Additionally, when paired with an EOS R-series camera that has In-Body Image Stabilization (IBIS), the Coordinated IS system allows for up to six stops of camera shake. 

It comes with Nine-blade diaphragm to create a smooth and pleasing bokeh quality. Accepts rear insert-type gelatin filters, which are cut-to-size and inserted behind the rear lens element.  Its ASC (Air Sphere Coating) and SWC (Subwavelength Structure Coating) to reduce flare, ghosting, and other aberrations for increased contrast and color accuracy. FLC fluorine coating applied to the lens's surface effectively repels dust, water droplets, grease, and dirt, ensuring easy removal even when they adhere to the lens surface. This coating also endures a high frequency of lens surface wiping, and its anti-reflective effect contributes to the capture of clear images.